Generally, due to the output and efficiency of a high voltage battery, a driving-enabled distance of environment-friendly vehicles is shorter than conventional gasoline vehicles or diesel vehicles.
Moreover, technology for increasing an output of the high voltage battery is being developed for enhancing a driving distance. However, in an inverter which provides a power of the high voltage battery to a driving motor, all of the output of the high voltage battery should be processed by the inverter, and due to this, a high power part is needed.
That is, since higher power is needed compared to the related art, relevant power parts and connection elements are increasing in size.
For an electrical connection between power parts of the inverter, high power parts are connected to each other by using a bus bar, low power parts are connected to each other by using a wire, and bus bars are coupled to each other by using bolting.
However, by using a bolting coupling method, a space is limited in disposition of elements. Due to this, there is a problem where a total size of the inverter increases progressively, and moreover, since a deviation between workers is large, damage or a connection defect occurs in assembly.
Moreover, when a conventional bolting coupling structure between bus bars is applied, a space where a tool is provided is needed, and thus, internal power parts of the inverter are assembled as a stacking type.
That is, elements should be assembled one by one in the stacking type where some elements are disposed on a first layer and are assembled through bolting coupling and other elements are disposed on a layer disposed on the first layer and are assembled through bolting coupling, and should be coupled through bolting. For this reason, the disposition of elements is mainly fixed.
Moreover, for bolting coupling, a space where a tool is provided is needed in an upper portion, and a structure into which a nut is inserted is separately needed in a lower portion. Due to this, the cost increases.